Drop template draw:frames from the clones of the master pages

Seems that all <draw:frame>s with the presentation:class attribute other than date-time|footer|header|page-number in the master pages are just there to be copied over to the normal pages/slides.
So they could be simply removed, which then also resulted in all the "Click to edit the outline text format..." to no longer be displayed in the viewer, cmp. http://webodf.org/demo/slides/Viewer.js/#../libreoffice-2013-odfautotests.odp for the current state.

See also ODF 1.2 spec §19.389 presentation:class

Fixes #19 for me